pytorch 2.7.1

[SMillerDev]

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---

Continuing #229208, hoping to fix it for #211365

[SMillerDev]

    FileNotFoundError: [Errno 2] No such file or directory: '/private/tmp/pytorch-20250723-11017-2wanov/pytorch-v2.7.1/.ci/docker/ci_commit_pins/nccl-cu12.txt'
    error: subprocess-exited-with-error
    
    × Preparing metadata (pyproject.toml) did not run successfully.
    │ exit code: 1
    ╰─> See above for output.

[SMillerDev]

Linux:

  ==> ./test
  WARNING: All log messages before absl::InitializeLog() is called are written to STDERR
  E0000 00:00:1753298081.957776   43496 descriptor_database.cc:550] Invalid file descriptor data passed to EncodedDescriptorDatabase::Add().
  F0000 00:00:1753298081.957859   43496 descriptor.cc:2248] Check failed: GeneratedDatabase()->Add(encoded_file_descriptor, size) 
  *** Check failure stack trace: ***

ARM mac:

    /private/tmp/pytorch-20250723-10688-pygu2d/pytorch-v2.7.1/third_party/kleidiai/kai/ukernels/matmul/pack/kai_lhs_quant_pack_bf16p8x4_f32_neon.c:8:2: error: This file must be compiled for AArch64, FEAT_BF16.
        8 | #error This file must be compiled for AArch64, FEAT_BF16.
          |  ^
    1 error generated.

[SMillerDev]

Should we just skip this test on Linux x86? I don't really know how to fix it and it's blocking multiple updates now

[SMillerDev]

Adopted the second commit from #229206